Grading articles by weight



April 11, 1961 M. v. BLAKE GRADING ARTICLES BY WEIGHT Filer} Aug. 18,1958 4 Sheets-Sheet l V g I III! I! 0/ m A April 11, 1961 M. v. BLAKEGRADING ARTICLES BY WEIGHT Flled Aug. 18, 1958 April 11, 1961 M. V.BLAKE 2,979,201

GRADING ARTICLES BY WEIGHT Filed Aug. 18, 1958 4 Sheets-Sheet 3 IN NTORn p vVAu HAN FAK q'huLuJ ATTVF April 11, 1961 M. v. BLAKE 2,979,201

GRADING ARTICLES BY WEIGHT Filed Aug. 18, 1958 4 Sheets-Sheet 4 MENTORMHVDEIV VAU HAIV Bi -AWE BY MMQLW 2,979,201 lcg Patented A3l'.-11, 19.61

GRADING ARTICLES BY WEIGHT Minden Vaughan Blake, *Carnanton, WoodlandsRoad E,

Virginia Water, England Filed Aug. 18, 1958, Ser. No. 755,645

19 Claims. (Cl. 209-121).

This invention relates to apparatus for grading articles by Weight. As aparticular example, the apparatus may be used for grading eggs but itwill readily be apparent that it may be used for grading other articlesthe Weight or" which varies over a limited range.

According to this invention, apparatus for grading articles by weightcomprises a beam pivoted about a horizontal axis and having acounterweight arranged to urge a downwardly-extending arm of the beamtowards the end of a feed system, which feed system includes means forfeeding articles singly into a releasable holder on that arm, a latchfor holding the beam when the arm is swung into a position adjacent thefeed system, means operative when an article has been fed into saidholder to release the latch so that, due to the weight of the article,the downwardly-extending arm of the beam swings away from the feedsystem, and release means operative when the beam reaches the otherextreme of its swing or shortly afterwards to release the article fromthe holder, the beam being arranged so that the centre of mass of thedownwardly-extending arm and the article to be carried thereby isoif-set from the line through the centre of mass of the counterweightarm and pivot axis so that the extent of the swing and hence the pointat which the article is dropped depends on the weight of the article. Itwill be seen with this arrangement that the article is fed into theholder and the weight of the article then causes the beam to swing. Theextent of the swing depends on the weight of the article and hence thearticle is released at a point depending on its weight. After therelease of the article, the downwardly-extending arm, under the actionof the counterweight, swings back to the feed system for the next cycleof operation. Suitable guide systems may be provided in the region wherearticles may be released from the holder so that the articles are fedinto separate containers or the like depending on where the articles aredropped thereby sorting the articles according to weight.

The aforementioned means for feeding articles singly into said holdermay comprise a rotatable carrier controlled by an escapement mechanismwhich escapement mechanism is actuated by said arm as the latterapproaches the end of the feed system so as to release the rotatablecarrier for rotation under gravitational force due to an article orarticles carried thereby.

Conveniently the escapement mechanism is gravityoperated so as to tendto rest in a position locking the rotatable carrier against furtherrotation.

The aforementioned rotatable carrier may be arranged, on rotation afterrelease by the escapement, to feed an article into said holder on thedownwardly-extending arm and then to release the aforementioned latch soas to permit the arm to swing away from the end of the feed system.

The rotatable carrier, which is preferably arranged for rotation about ahorizontal axis, is preferably formed with four carrier arms evenlyspaced around its axis and arranged so that it can be locked by theescapement in any of four equally spaced positions. The rotatablecarrier can then be arranged with respect to the remainder of the feedsystems so that it carries either one or two of the articles on armslying in positions tending to rotate the carrier in the requireddirection, thereby ensuring that when an article has been fed on to theholder on the arm there is a second article on the rotatable carriertending to rotate it to effect the release of the latch. This latch mayconveniently be operated by cam surfaces on the-rotatable carrier;

The aforementioned feed system may, for articles which will roll, suchas eggs, comprise a sloping runway arranged sloping downwardly to feedthe articles to the rotatable carrier. In an egg-grader, this runway maycomprise two parallel rails, preferably covered with resilient materialsuch as rubber and spaced apart sufficiently that the eggs will rolldown the rails towards the rotatable carrier. A gate may be provided inthe runway operated by the rotatable carrier to release the articles oneat a time onto the rotatable carrier.

The aforementioned holder may comprise two pairs of inwardly directedfingers arranged to form a cradle for the article, one of the pairs offingers being pivotally mounted so as to be movable away from the otherpair a suflicient distance to cause the article to drop when the articleis to be released. This movement of the fingers may be effected by apawl which on the forward swing of the arm, that is away from the feedsystem, rides over fixed abutments but engages one of these abutments asthe main beam arm starts to swing back towards the end of the feedsystem.

The beam is preferably supported on knife edges. The mass andpositioning of the counterweight will determine the extent of swing ofthe beam and this counterweight may be carried on an upwardly-extendingarm of the beam which may be arranged at an angle with respect to thedownwardly-extending arm. The counterweight may be adjustable inposition on the upwardly-extending arm for setting up the apparatus.This counterweight preferably is made adjustable not only towards andaway from the axis of rotation but also angularly about the axis ofrotation. Suitable locking means may be provided to prevent anyaccidental movement of the counterweight.

The following is a description of one embodiment of the inventioncomprising an apparatus for grading eggs by weight, reference being madeto the accompanying drawings in which Figure 1 is a view in sideelevation of the apparatus;

Figure 2 is a perspective view of the swinging beam of the apparatus ofFigure 1;

Figure 3 is a plan view of the apparatus of Figure 1;

Figure 4 is a view in side elevation of part of the apparatus of Figure1, this view being to a larger scale than Figure 1 and showing theapparatus from the opposite side;

T Figure 5 is a plan View to a larger scale of the apparatus of Figure 4looking in the direction of the arrow A;

Figure 6 is a section along the line 66 of Figure 5; 1

Figures 7 to 13 are diagrammatic illustrations for explaining theoperation of the apparatus of Figures 1 to 6, the Figures 7 to 13illustrating successive stages in the operation of the apparatus; and

Figures 14 and 15 illustrate the operation of a release mechanism.

Referringto Figures 1 to 6 of the drawings the apparatus has a base 10which is provided with levelling indicators 11 and adjustable feet 12for levelling purposes. On this base is arranged a sloping runway formedof Ltwo parallel metal rails 13, which rails are covered with rubber.The runway slopes downwardly at a small angle just suificient to alloweggs to roll down the runway. An

electric strip lamp 14 is mounted beneath the runway between the rails13 for candling the eggs as they pass along the runway. Extendingupwardly from the base near the lower end of the runway are a pair ofsupports 15 rigidly secured to the base and carrying at their upper endsbearing surfaces 16 for a pair of knife edges 17 which are mounted oneon each side of a swingable beam 18. This beam, which is most clearlyshown in Figure 2, is formed of a pair of angle section members 19 whichare spaced apart and has, with respect to the pivot axis, a longer armand a shorter arm. The longer arm is capable of swinging downwardly froma position in which it is about 45 to the vertical to a position justbeyond the vertical. This latter position is shown in chain lines at 20in Figure 1. The upper arm carries a counterweight 21 which is arrangedso that when the lower arm is at the extreme limit of its swing justbeyond the vertical, the counterweight is immediately above the pivotaxis. This counterweight is mounted on a threaded rod 22 so as to beadjustable away from and towards the pivot axis of the knife edges 17.The outer end of this threaded rod 22 is supported by a member 23movable transversely to the pivot axis by means of an adjusting screw24, thereby enabling the axial direction of the threadedcounterweightcarrying rod 22 to be adjustable angularly about the pivotaxis. As will be apparent from the following description, the centre ofmass of the downwardly-extending arm'of the beam 18 and the egg carriedthereby has to be off-set from the plane through the pivot axis and thecentre of mass of the counterweight 21 and counterweight arm. At thelower end of the downwardly-extending arm, the two angle section members19 are turned inwardly towards one another to constitute a first pair offingers 25 forming part of an egg-holder on the arm. Mounted on a shaft26 pivoted in the two angle section members 19 for pivotal movementabout an axis parallel to the pivot axis of the knife edges 17 are afurther pair of fingers 27 which extend in a direction generally atright angles to their pivot axis and towards the inner ends of the firstpair of fingers 25. The two fingers 27 are slightly curved and the fourfingers 25, 27 together form a cradle suitable for carrying an egg, asindicated by the chain lines 28 in Figure 2, when the fingers 27 are inthe position nearest the fingers 25. The pivoted fingers 27 are urgedtowards the fingers 25 by a light counterweight 30 and are normally heldin that position by a spring-loaded catch 31. This catch is urged into aposition engaging a cross member 32 between the two fingers 27 by meansof a helical spring 33 around a shaft 34 on which the catch 31 issecured. This catch is mechanically coupled to a pawl 35 at one side ofthe downwardly-extending arm of the main beam 18, the catch 31 and pawl35 both being mounted on the shaft 34. This pawl 35 is positioned toengage fixed abutments 36 on the base of the apparatus. As is mostclearly shown in Figure 1 these abutments 36 are arranged so that as thedownwardly-extending arm of the beam 18 swings away from the feed systemconstituted by the aforementioned runway, the pawl 35 rides over theseabutments 36 and is not operated until the downwardlyextending arm ofthe beam 18 begins to swing back whereupon the pawl 35 will engage thefirst of the abutments 36 it meets and it will thus lift up and sorelease the catch 31. On release of the catch 31 the fingers 27 are nowfree to move and the weight of the egg on the fingers 25, 27 moves thepivoted pair of fingers 27 away from the other pair as shown in fulllinesin Figure 1, so that the egg drops down between the four fingers25, 27. After the egg has been released, the counterweight 30 for thepiovted fingers 27 moves these pivoted fingers towards the fingers 25and, after the pawl 35 has moved clear of the abutments 36 on thebackward swing of the main beam 18, the catch 31 returns under theaction of its spring 33 to its normal position securing the four fingers25, 27 together in the position forming a cradle for receiving the nextegg.

The feed system for feeding eggs into the holder on the end' of the armconstituted by the four fingers 25, 27, comprises a rotatable carrier 40which is most clearly illustrated in Figures 4 and 5. This rotatablecarrier 40 is rotatable about a horizontal axis just below the lower endof the sloping runway 13 and comprises a shaft 41 from which extend fourradial egg-carrying arms 42 which arms on rotation pass between the tworails 13 at thelower end of the runway, the arms 42 extending beyond theend of these rails. An escapement mechanism 44 is mounted on one of thefixed supports 15 which extend upwardly from the base to carry the beamknife edges 17, this escapement mechanism comprising a pivotedescapement member 45 co-operating with the four radial arms 46 securedon one end of the carrier shaft 41, the escapement member having acounterweight 47 formed by an upward extension of the escapement member45 beyond its pivot axis tending to bring the escapement member 45 intoposition in the path of the ends of the arms 46, so preventing therotatable carrier 40 from rotating in the direction in which it will beurged by the eggs coming down the runway. In Figure 4 theescapement'member 45 is shown in this position with a latching portion48 engaging one of the arms 46. The escapement mechanism 44 is arrangedso that the egg-carrying arms 42 of the rotatable carrier 40, which aremutually at right angles, are locked from further rotation at positionsjust before these arms have reached horizontal and vertical directionsas shown in Figure 4. The counterweight 47 for the escapement mechanism44 is positioned so that it is engaged by the downwardly-extending armof the main beam 18 as the latter is swinging back towards the end ofthe runway so that the escapement is released just before this arm ofthe beam 18 reaches its uppermost position. As this arm of the beam 18reaches its uppermost position adjacent the rotatable carrier 40, thetwo inwardly directed fingers 25 forming the fixed part of the cradlefor the egg on the beam ride up a pair of spring-loaded fingers 50forming latches mounted on the two arms 51 of a U-shaped member 52. Thismember 52 is pivoted about a horizontal axis through the base of the Uby means of a shaft 53 extending between the aforementioned supports 15.The fingers 25 of the cradle press these spring-loaded latch fingers 50downwardly until the cradle fingers 25 have passed over the ends of thelatch fingers 50 which thereupon rise under the spring force to engagebehind the cradle fingers 25 so thereby locking the main beam arm 18against any return swing.

The two arms 51 of the U-shaped member are shaped as shown at 54inFigure 6 to engage cam surfaces 55 on the aforementioned shaft 41carrying the rotatable carrier 40. Conveniently the two arms 51 of the Ulie outside the two rails 13 of the runway as is most clearly seen inFigure 5. The cam surfaces 55 on the shaft 41 are shaped so that as therotatable carrier 40 turns from the position in which it has been lockedby the escapement after release, that is to say the position shown inFigure 4, the arms 51 of the U are dropped, so bringing the springloaded latch fingers 50 out of engagement with the cradle fingers 25permitting the main beam arm to swing down again. Further rotation ofthe rotatable carrier 40 brings the arms 51 of the U-shaped member 52upwardly so that after the shaft 41 has turned through the spring loadedlatch fingers 50 are ready to latch the main beam 18 on the next returnswing. The operation is thus cyclic with four latching positionscorresponding to the four egg carrying arms42 of the rotatable carrier40, and the cam surfaces 55 on the shaft 41 are shaped to lift the arms51 four times in each revolution of the shaft.

The operation of the apparatus thus far described is as follows:assuming that the main beam arm is held in a downwardly-extendingposition, an egg may be placed on the horizontal extending arm 42 of therotatable carrier 40 which extends towards the swinging beam 18, that isto say the arm extending to the left in Figure 5. This position of therotatable carrier 40 is illustrated diagrammatically in Figure 7 whichshows an egg 65 on the horizontal extending arm 42 of the carrier. Thecarrier 40 is locked by the escapement 44 and a further egg 66 may beplaced behind the next arm 42 of the carrier 40, that is the arm whichis extending upwardly between the rails 13 of the runway. The next egg67 on the sloping runway rails 13 is held back by a gate member 60 to bedescribed later and does not afiect the operation of the apparatus atthis stage. As shown in the drawings, the egg carrying arms 42 areshaped so that the horizontally extending arm remote from the runwaycurves upwardly slightly at its outer end to hold the egg securely.Further eggs may be loaded along the runway behind the egg 67. The eggswhich are loaded initially into the apparatus would, of course, becandled before being put on. When the machine is operating the eggswould be loaded on the runway and would be examined as they passed alongthe runway over the candling lamp 14. After the apparatus has beeninitially loaded, the main beam arm is then allowed to swing upwardly asindicated by the arrow 68 in Figure 7 under the influence of itscounterweight 21 and it will engage the escapement counterweight 47 asshown in Figure 8 so releasing the rotatable carrier 40 as shown inFigure 9. The carrier 44) will slowly start to move but, as the mainbeam arm is swinging upwardly, this arm will rapidly ride over thespring-loaded latch fingers 50 as shown in Figures 8 and 9 and, justbeyond the position shown in Figure 9, will momentarily be latchedbefore the carrier 40 has rotated appreciably. A buffer 49 is providedto take any impact. The subsequent rotation of the carrier 40 willfirstly cause the horizontally extending arm 42 of the carrier carryingthe egg to pass between the fingers of the cradle at the end of the beam18 so depositing the egg in this cradle as shown in Figure 10 and willthen (by the action of the cam surfaces 55) release the U-shaped member52 as shown in Figures 10 and 11 so releasing the latch for the mainbeam arm. Under the weight of the egg in the cradle on the beam 18,which weight overcomes the effect of the counterweight 21, the beam armwill then swing downwardly as shown in Figures 10, ll, 12 and 13, theswing continuing to an extent depending on the weight of the egg and,immediately after it begins its return swing, the pawl 35 for the cradlecatch 31 will be operated by the first of the fixed abutments 36 whichit engages so releasing the egg at a position depending on the weightofvthe egg. The fixed abutments 36 are illustrated in plan in Figure 14and, together with the pawl 35 are shown in side elevation in Figure 15.In these figures, the beam moves from left to right in swinging awayfrom the feed system and the pawl rides over the abutments while movingin this direction. As soon as the beam starts to swing back againhowever, the pawl 35 engages one of the abutments, the particular oneengaged depending on the extent of the swing. The resultant movement ofthe pawl 35 releases the egg from the holder. The base of the apparatusin the region below the beam is provided with a padded surface 56 e.g. abaize covered surface which lies closely under the beam so that the eggdrops only a short distance. This surface is provided with a number ofridges 57 defining guide channels and has a slope so that eggs droppedin different positions along the path of the lower end of the beam 18,that is eggs of different weights, will be fed into the separate guidechannels and will roll down these channels into suitable receptacles 53.As the main beam arm swings upwardly under the influence of thecounterweight 21 the cradle holder will be closed and locked by thecatch 31 as previously described. In the meantime the next egg 66 on thecarrier 49 has moved the carrier, under the weight of that egg, as shownin Figures 10, ll, 12 and 13, the carrier ultimately moving into theposition corresponding to that shown in Figure 7 so that the egg 66 ison the horizontally extending arm and the carrier 6 The next egg 67 onthe runway has rolled forward to bear against the next arm 42 of thecarrier 40 which arm has now moved into the upward direction. The mainbeam arm swinging upwardly then releases the escapement 44 and the cycleoperation is repeated.

In order to prevent any possibility of two eggs rollin into the regionbetween a pair of arms 42 of the rotatable carrier 40, a gate isprovided comprising a bell-crank shaped member 60 (see Figure 5)pivotally mounted between the runway rails 13 with the pivot axis 61 atthe junction of the two arms of the member 60. This member 6%) has anupwardly directed gate arm which may be U-shaped as shown in Figures 3and 5 serving'to hold back the line of eggs on the runway. The other arm62 of this gate member extends over the ends of upwardly moving arms 42of the rotatable carrier 40. The rotation of the carrier 4-0 thus liftsthe arm 62 and so swings the gate arm downwardly as shown in Figure 12to permit an egg to roll towards the carrier arm 42. The gate member 60is arranged so that under the influence of gravity the gate arm isnormally in its upper position so preventing the movement of eggs fromthe runway to the carrier 40 and it thus returns automatically toprevent the next egg 68 on the runway from affecting the operation ofthe apparatus.

The apparatus may be calibrated experimentally and the aforementionedabutments for releasing the cradle catch 31 are adjustably mounted on amember 70 so as to be adjustable along the line of swing of the mainbeam arm. For ensuring the release of particularly heavy eggs withoutexcessive swing of the beam there may be provided a fixed abutment 71which engages a further arm 72 mounted on the cradle operating shaft 3 5so that, as the downwardly-extending beam arm swings just beyond thevertical, the catch 31 is released on the upward swing of the arm. Assoon as the egg is dropped from the cradle on the beam arm, thecounterweight 21 will rapidly stop any further outward movement causingthe arm to swing back towards the feed system.

I claim:

1. Apparatus for grading articles by weight comprising a support, a beampivoted on said support about a horizontal axis and having a downwardlyextending arm and a counterweight arm, a releasable holder on saiddownwardly extending arm, a feed system positioned so that thecounterweight arm urges said downwardly extending arm towards said feedsystem, which feed system includes means for feeding articles singlyinto said releasable holder, a latch for holding the beam when saiddownwardly extending arm is swung into a position adjacent the feedsystem, means operative when an article has been fed into said holder torelease the latch so that due to the weight of the article thedowwnardly extending arm of the beam swings away from the feed system,and release means on said downwardly extending arm operative when thebeam reaches the other extreme of its swing or shortly afterwards torelease the article from said holder, the beam being arranged so thatthe center of mass of the downwardly extending arm and the article to becarried is at a point, in the plane of movement of the beam, which isoff-set from a plane through the pivot axis and the center of mass ofthe counterweight arm so that the extent of swing and hence the point atwhich the article is dropped depends on the weight of the article.

2. Apparatus as claimed in claim 1 wherein guide systems are provided inthe region where articles are released from the holder so that articlesare fed into separate containers depending on where the articles aredropped thereby sorting the articles according to weight.

3. Apparatus as claimed in claim 1 wherein said means for feedingarticles singly into said holder comprises a rotatable carriercontrolled by an escapement mechanism which escapement mechanism isactuated by said downwardly extending arm as the latter approaches islocked against further rotation by the escapement-44. 75 the end of thefeed system so as to release the rotatable carrier for rotation undergravitational force due to the weight of an article carried thereby.

4. Apparatus as claimed in claim 3 wherein the escapement mechanism isgravity-operated so as to tend to rest in a position locking therotatable carrier against further rotation.

5. Apparatus as claimed in claim 3 wherein the said rotatable carrier isarranged, on rotation after release by the escapement, to feed anarticle into said holder on the downwardly-extending arm and then torelease said latch so as to permit the arm to swing away from the end ofthe feed system.

6. Apparatus as claimed in claim 3 wherein said rotatable carrier isarranged for rotation about a horizontal axis.

7. Apparatus as claimed in claim 6 wherein said rotatable carrier isformed with four carrier arms evenly spaced around its axis and arrangedso that it can be locked by the escapement in any of four equally spacedpositions.

8. Apparatus as claimed in claim 7 wherein said rotatable carrier isarranged with respect to the remainder of the feed system so that itcarries either one or two of the articles on arms lying in positionstending to rotate the carrier in the required direction to ensure that,when an article has been fed onto the holder on the arm, there is asecond article on the rotatable carrier tending to rotate it to efiectrelease of the latch.

9. Apparatus as claimed in claim 8 wherein said means operative torelease the latch comprise cam surfaces on the rotatable carrier.

10. Apparatus as claimed in claim 3 and for use for grading articleswhich will roll, wherein said feed system comprises a sloping runwayarranged to feed the articles to the rotatable carrier.

11. Apparatus as claimed in claim 10 and arranged as an egg grader, saidrunway comprising two parallel rails 'spaced apart sufficiently that theeggs will roll down the rails towards the rotatable carrier.

12. Apparatus as claimed in claim 10 wherein a gate is provided in therunway operated by the rotatable carrier to release the articles one ata time onto the rotatable carrier.

13. Apparatus as claimed in claim 1 wherein said holder comprises twopairs of inwardly'directed fingers arranged to form a cradle for thearticle, one of the pairs of fingers being pivotally mounted so as to bemovable away from the other pair a suflicient distance to cause thearticle to drop when the article is to be released.

14. Apparatus for grading articles by weight comprising a support, abeam pivoted on said support about a horizontal axis and having adownwardly extending arm and a counterweight arm, a releasable holder onsaid downwardly extending arm, which holder comprises two pairs ofinwardly directed fingers arranged to form a cradle for the article, oneof the pairs of fingers being pivotally mounted on said downwardlyextending arm to be movable away from the other pair a sufiicientdistance to cause the article to drop when the fingers are moved apart,a feed system positioned on said support with respect to said beam sothat the counterweight arm urges said downwardly extending arm towardssaid feed system, which feed system includes means for feeding articlessingly into said holder, a latch for holding the beam when saiddownwardly extending arm is swung into a position adjacent the feedsystem, means operative when an article has been fed into said holder torelease the latch so that due to the weight of the article thedownwardly extending arm of the beam swings away from the feed system, aset of fixed abutments on said support, a pawl on said downwardlyextending arm operatively connected to said pivotally mounted pair offingers arranged to ride over said fixed abutments as said downwardlyextending arm swings away from the feed system but to engage one ofthese abutments as the arm starts to swing back towards the end of thefeed system and thereby to move said pair of fingers to release thearticle from said holder, the beam being arranged so that the center ofmass of the downwardly extending arm and the article to be carried is ata point, in the plane of movement of the beam, which is oflE-set from aplane through the pivot axis and the center of mass of the counterweightarm so that the extent of swing and hence the point at which the articleis dropped depends on the weight of the article.

15. Apparatus for grading articles by weight comprising a support, abeam pivoted on said support about a horizontal axis and having adownwardly extending arm and an upwardly extending arm, a counterweighton said upwardly extending arm, a releasable holder on said downwardlyextending arm, a feed system positioned on said support with respect tosaid beam so that said counterweight urges said downwardly extending armtowards said feed system, which feed system includes means for feedingarticles singly into said holder, a latch for holding the beam when saiddownwardly extending arm is swung into a position adjacent the feedsystem, means operative when an article has been fed into said holder torelease the latch so that due to the weight of the article thedownwardly extending arm of the beam swings away from the feed system,and release means on said downwardly extending arm operative when thebeam reaches the other extreme of its swing or shortly afterwards torelease the article from said holder, the beam being arranged so thatthe center of mass of the downwardly extending arm and the article to becarried is at a point, in they plane of movement of the beam, which iself-set from a plane through the pivot axis and the center of mass ofthe counterweight and counterweight arm so that the extent of swing andhence the point at which the article is dropped depends on the weight ofthe article.

16. Apparatus as claimed in claim 15 wherein adjustable mounting meansfor the counterweight are provided on said counterweight arm foradjusting the position of the counterweight towards and away from saidhorizontal axis and angularly about said horizontal axis.

17. Apparatus as claimed in claim 16 wherein locking means are providedto prevent any accidental movement of the counterweight relative to saidbeam.

18. Apparatus for grading articles by weight comprising a support, abeam pivotally mounted on said support for swinging about a horizontalaxis, said beam having a holder for an article and also having acounterweight to urge the beam to a loading position when the holder isempty, the counterweight being such that the weight of the article whenloaded into the holder moves the beam away from the loading position, afeeder on said support for feeding articles singly into said holder, alatch operative to latch the beam when it swings to the loadingposition, means operative when an article has been fed into said holderto release the latch, and release means on said beam operative, when thebeam has swung away from said loading position and starts to swing back,to release the article from said holder.

19. Apparatus as claimed in claim 18 wherein said holder comprises aplurality of fingers forming a cradle, at least one pair of fingersbeing movable to allow an article to fall out of the holder, and whereinsaid release means comprises a pawl operatively connected to the movablefingers and wherein cooperating fixed abutments are provided on saidsupport, the pawl being arranged to ride over said fixed abutments assaid beam swings away from the loading position but to engage one of theabutments as the beam starts to swing back towards the loading positionand thereby to move said movable fingers to release the article from theholder.

Swartz May 30, 1939 Hill June 1, 1948

